[jstanley]

Visa is a company and produces profit from people using it, and the people using it don't need to be shareholders, so if you're the only shareholder, you're not reducing the utility for anyone else.

If you own all of the cryptocurrency in the world, nobody else can use it. Obviously it becomes worthless. The same would be true of any currency. That's just a small part of what makes a currency different to a company.